Testosterone (Free) , Serum (Equilibrium Ultrafiltration) With Total Testosterone - (LABCORP)
Testosterone levels decrease normally with age. This may cause men to have erectile problems or to lose interest in sex. This test will determine the level of free and total testosterone.
Use of synthetic steroids, various supplements and/or high doses of biotin may interfere with the accuracy of the standard immunoassay Testosterone Total serum test. If you are taking any of these it is recommended that you order the Testosterone, Total, Women, Children, and Hypogonadal Males, LC/MS-MS for testing.
Percent Free Testosterone
Note: If total testosterone levels are greater than the cutoff for this test (>1500), results for free testosterone and/or percent free testosterone may not be provided. If total testosterone results are expected to be >1500 it is best that the LC/MS-MS version of this test be ordered.
If using a testosterone cream please be sure you have not rubbed any into the antecubital area of your arm for the last 24 hours as it can give elevated results. This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H or coenzyme R). It is recommended to stop biotin consumption at least 72 hours prior to the collection of specimen.
Estimated turnaround for results is 5 business days. If confirmation testing is required, the estimated time may be extended.